The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
P. C. M. Van Noort - One of the best experts on this subject based on the ideXlab platform.
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In vivo exposure of Dreissena polymorpha mussels to the quinones menadione and Lawsone: menadione is more toxic to mussels than Lawsone.
Journal of applied toxicology : JAT, 2004Co-Authors: A. M. Osman, S. G. P. Rotteveel, P.j. Den Besten, P. C. M. Van NoortAbstract:The principal aim of this study was to assess whether the two quinones, menadione (2-methyl-1,4-naphthoquinone) and Lawsone (2-hydroxy-1,4-naphthoquinone), elicit differential toxicity in mussels as has been reported for higher organisms. Therefore, the effects of short-term (48 h) and long-term (20 days) exposure of the two quinones at concentrations of 0.56 and 1 mg l−1 to zebra mussels, Dreissena polymorpha, under laboratory conditions were studied. After the short-term exposure, the specific activities of the two-electron quinone oxidoreductase (DT-diaphorase) and the one-electron catalysing quinone reductases NADPH-cytochrome c reductase and NADH-cytochrome c reductase were determined in the gills and the rest of the soft tissues (soft mussel tissues minus the gills) of both treated and control mussels. At the higher concentrations of menadione and Lawsone used, a significant reduction of the activity of NADPH-cytochrome c reductase in the gills and in the rest of the soft mussel tissues (by 33–34% and 31–43%, respectively) was observed. The activities of DT-diaphorase and NADH-cytochrome c reductase were not significantly affected. Interestingly, DT-diaphorase was observed in the gills, an organ requiring protection against antioxidants. Furthermore, a single-cell electrophoretic assay (comet assay) performed with gill cells to assess DNA damage by the quinones did not show any significant difference between the treated and the control organisms. This indicates that the formation of reactive species by the quinone metabolism in vivo in the mussels was possibly suppressed through the concerted action of DT-diaphorase and antioxidant enzymes. The results of in vitro experiments with gill extracts confirmed the protective role of DT-diaphorase. The rate of the two-electron quinone reduction was found to be five times that of the one-electron quinone reduction. The results of the long-term exposure unambiguously demonstrated that in mussels menadione, unlike in higher organisms, is more toxic than Lawsone. The lack of detectability of xanthine oxidase in the mussel tissues could explain the comparatively lower toxicity of Lawsone in the invertebtrate, lending support to a previous suggestion that xanthine oxidase might be responsible for the mechanism of toxicity of Lawsone in higher organisms in vivo. Copyright © 2004 John Wiley & Sons, Ltd.
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evidence for redox cycling of Lawsone 2 hydroxy 1 4 naphthoquinone in the presence of the hypoxanthine xanthine oxidase system
Journal of Applied Toxicology, 2003Co-Authors: A. M. Osman, P. C. M. Van NoortAbstract:This study reports that Lawsone (2-hydroxy-1,4-naphthoquinone) undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system. The rate of cytochrome c reduction obtained in the presence of 80 µM Lawsone was almost three times the rate of cytochrome c reduction measured in its absence. This increase in the rate of cytochrome c reduction was partially inhibited by superoxide dismutase, suggesting the involvement of O2•− in this process. It is remarkable to note that, even though Lawsone is considered to be a non-redox-cycling quinone in vitro, this quinone was shown to be more toxic in vivo in rats than menadione, causing haemolytic anemia of an oxidative nature and renal damage. The view that this quinone is a non-redox-cycling quinone was based on the inability of one-electron-transferring flavoenzymes such as NADPH-cytochrome c reductase to reduce this naphthoquinone. Our finding that Lawsone, like menadione, undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system could explain the observed oxidative damage of tissues inflicted by this quinone in rats in vivo. Such an observation therefore reconciles the in vivo toxicity results of this naphthoquinone with those of in vitro experiments. Copyright © 2003 John Wiley & Sons, Ltd.
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Evidence for redox cycling of Lawsone (2-hydroxy-1,4-naphthoquinone) in the presence of the hypoxanthine/xanthine oxidase system.
Journal of applied toxicology : JAT, 2003Co-Authors: A. M. Osman, P. C. M. Van NoortAbstract:This study reports that Lawsone (2-hydroxy-1,4-naphthoquinone) undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system. The rate of cytochrome c reduction obtained in the presence of 80 µM Lawsone was almost three times the rate of cytochrome c reduction measured in its absence. This increase in the rate of cytochrome c reduction was partially inhibited by superoxide dismutase, suggesting the involvement of O2•− in this process. It is remarkable to note that, even though Lawsone is considered to be a non-redox-cycling quinone in vitro, this quinone was shown to be more toxic in vivo in rats than menadione, causing haemolytic anemia of an oxidative nature and renal damage. The view that this quinone is a non-redox-cycling quinone was based on the inability of one-electron-transferring flavoenzymes such as NADPH-cytochrome c reductase to reduce this naphthoquinone. Our finding that Lawsone, like menadione, undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system could explain the observed oxidative damage of tissues inflicted by this quinone in rats in vivo. Such an observation therefore reconciles the in vivo toxicity results of this naphthoquinone with those of in vitro experiments. Copyright © 2003 John Wiley & Sons, Ltd.
Ulrike Zedler - One of the best experts on this subject based on the ideXlab platform.
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The Henna pigment Lawsone activates the Aryl Hydrocarbon Receptor and impacts skin homeostasis
Scientific Reports, 2019Co-Authors: Laura Lozza, Pedro Moura-alves, Teresa Domaszewska, Carolina Lage Crespo, Ioana Streata, Annika Kreuchwig, Andreas Puyskens, Marina Bechtle, Marion Klemm, Ulrike ZedlerAbstract:As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo. In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes. The skin acts as an important first barrier of the body, which is constantly exposed to diverse environmental and mechanical insults, such as pollution, infection, injury and radiation, amongst others 1. Additionally, the application of cosmetics and other agents can have a major impact on skin homeostasis 1. Among the most widely used skin dyes, are the extracts of Lawsonia inermis, commonly known as Henna 2. In traditional medicine, Henna has been widely used to treat bacterial and fungal infections, inflammation, cancer and various skin pathologies 3 , but the underlying mechanisms remain insufficiently understood. Major side effects of Henna preparations are caused by the additive para-phenylenediamine (PPD) that has been associated with allergic contact dermatitis 4,5. As natural product, Henna comprises a mixture of numerous compounds most of which are poorly characterized opeN There are amendments to this paper
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The Henna pigment Lawsone activates the Aryl Hydrocarbon Receptor and impacts skin homeostasis
Scientific Reports, 2019Co-Authors: Laura Lozza, Pedro Moura-alves, Teresa Domaszewska, Carolina Lage Crespo, Ioana Streata, Annika Kreuchwig, Andreas Puyskens, Marina Bechtle, Marion Klemm, Ulrike ZedlerAbstract:As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. Tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo . In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes.
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The Aryl Hydrocarbon Receptor senses the Henna pigment Lawsone and mediates Yin-Yang effects on skin homeostasis
2018Co-Authors: Laura Lozza, Pedro Moura-alves, Teresa Domaszewska, Ioana Streata, Annika Kreuchwig, Marina Bechtle, Marion Klemm, Ulrike Zedler, Carolina Lage Crespo, Silviu Ungureanu BogdanAbstract:As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. Tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo. In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes.
A. M. Osman - One of the best experts on this subject based on the ideXlab platform.
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In vivo exposure of Dreissena polymorpha mussels to the quinones menadione and Lawsone: menadione is more toxic to mussels than Lawsone.
Journal of applied toxicology : JAT, 2004Co-Authors: A. M. Osman, S. G. P. Rotteveel, P.j. Den Besten, P. C. M. Van NoortAbstract:The principal aim of this study was to assess whether the two quinones, menadione (2-methyl-1,4-naphthoquinone) and Lawsone (2-hydroxy-1,4-naphthoquinone), elicit differential toxicity in mussels as has been reported for higher organisms. Therefore, the effects of short-term (48 h) and long-term (20 days) exposure of the two quinones at concentrations of 0.56 and 1 mg l−1 to zebra mussels, Dreissena polymorpha, under laboratory conditions were studied. After the short-term exposure, the specific activities of the two-electron quinone oxidoreductase (DT-diaphorase) and the one-electron catalysing quinone reductases NADPH-cytochrome c reductase and NADH-cytochrome c reductase were determined in the gills and the rest of the soft tissues (soft mussel tissues minus the gills) of both treated and control mussels. At the higher concentrations of menadione and Lawsone used, a significant reduction of the activity of NADPH-cytochrome c reductase in the gills and in the rest of the soft mussel tissues (by 33–34% and 31–43%, respectively) was observed. The activities of DT-diaphorase and NADH-cytochrome c reductase were not significantly affected. Interestingly, DT-diaphorase was observed in the gills, an organ requiring protection against antioxidants. Furthermore, a single-cell electrophoretic assay (comet assay) performed with gill cells to assess DNA damage by the quinones did not show any significant difference between the treated and the control organisms. This indicates that the formation of reactive species by the quinone metabolism in vivo in the mussels was possibly suppressed through the concerted action of DT-diaphorase and antioxidant enzymes. The results of in vitro experiments with gill extracts confirmed the protective role of DT-diaphorase. The rate of the two-electron quinone reduction was found to be five times that of the one-electron quinone reduction. The results of the long-term exposure unambiguously demonstrated that in mussels menadione, unlike in higher organisms, is more toxic than Lawsone. The lack of detectability of xanthine oxidase in the mussel tissues could explain the comparatively lower toxicity of Lawsone in the invertebtrate, lending support to a previous suggestion that xanthine oxidase might be responsible for the mechanism of toxicity of Lawsone in higher organisms in vivo. Copyright © 2004 John Wiley & Sons, Ltd.
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evidence for redox cycling of Lawsone 2 hydroxy 1 4 naphthoquinone in the presence of the hypoxanthine xanthine oxidase system
Journal of Applied Toxicology, 2003Co-Authors: A. M. Osman, P. C. M. Van NoortAbstract:This study reports that Lawsone (2-hydroxy-1,4-naphthoquinone) undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system. The rate of cytochrome c reduction obtained in the presence of 80 µM Lawsone was almost three times the rate of cytochrome c reduction measured in its absence. This increase in the rate of cytochrome c reduction was partially inhibited by superoxide dismutase, suggesting the involvement of O2•− in this process. It is remarkable to note that, even though Lawsone is considered to be a non-redox-cycling quinone in vitro, this quinone was shown to be more toxic in vivo in rats than menadione, causing haemolytic anemia of an oxidative nature and renal damage. The view that this quinone is a non-redox-cycling quinone was based on the inability of one-electron-transferring flavoenzymes such as NADPH-cytochrome c reductase to reduce this naphthoquinone. Our finding that Lawsone, like menadione, undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system could explain the observed oxidative damage of tissues inflicted by this quinone in rats in vivo. Such an observation therefore reconciles the in vivo toxicity results of this naphthoquinone with those of in vitro experiments. Copyright © 2003 John Wiley & Sons, Ltd.
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Evidence for redox cycling of Lawsone (2-hydroxy-1,4-naphthoquinone) in the presence of the hypoxanthine/xanthine oxidase system.
Journal of applied toxicology : JAT, 2003Co-Authors: A. M. Osman, P. C. M. Van NoortAbstract:This study reports that Lawsone (2-hydroxy-1,4-naphthoquinone) undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system. The rate of cytochrome c reduction obtained in the presence of 80 µM Lawsone was almost three times the rate of cytochrome c reduction measured in its absence. This increase in the rate of cytochrome c reduction was partially inhibited by superoxide dismutase, suggesting the involvement of O2•− in this process. It is remarkable to note that, even though Lawsone is considered to be a non-redox-cycling quinone in vitro, this quinone was shown to be more toxic in vivo in rats than menadione, causing haemolytic anemia of an oxidative nature and renal damage. The view that this quinone is a non-redox-cycling quinone was based on the inability of one-electron-transferring flavoenzymes such as NADPH-cytochrome c reductase to reduce this naphthoquinone. Our finding that Lawsone, like menadione, undergoes redox cycling in the presence of the hypoxanthine/xanthine oxidase system could explain the observed oxidative damage of tissues inflicted by this quinone in rats in vivo. Such an observation therefore reconciles the in vivo toxicity results of this naphthoquinone with those of in vitro experiments. Copyright © 2003 John Wiley & Sons, Ltd.
Habib M Pathan - One of the best experts on this subject based on the ideXlab platform.
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dye sensitized solar cell with Lawsone dye using a zno photoanode experimental and td dft study
RSC Advances, 2015Co-Authors: Shubhangi Khadtare, Sunita Salunkegawali, Anuja P Ware, Sandesh Jadkar, Subhash S Pingale, Habib M PathanAbstract:The spectral features of Lawsone (2-hydroxy-1,4-naphthoquinone), an active component of the natural dye henna, are analyzed in ethanol using experimental and computational methods. The calculated UV-Vis absorption spectrum from the time-dependent density functional theory (TD-DFT) approach is compared with the experimental results, allowing a detailed assignment of the UV-Vis spectral features based on molecular orbitals. Further, we have analyzed the light intensity dependent J–V characteristics and electrochemical impedance spectrum of a dye sensitized solar cell fabricated with Lawsone and a ZnO photoanode. The photovoltaic data of the sensitizer adsorbed on ZnO films exhibited a reasonable power conversion efficiency, i.e. 0.68% at 26 mW cm−2 light intensity.
Laura Lozza - One of the best experts on this subject based on the ideXlab platform.
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The Henna pigment Lawsone activates the Aryl Hydrocarbon Receptor and impacts skin homeostasis
Scientific Reports, 2019Co-Authors: Laura Lozza, Pedro Moura-alves, Teresa Domaszewska, Carolina Lage Crespo, Ioana Streata, Annika Kreuchwig, Andreas Puyskens, Marina Bechtle, Marion Klemm, Ulrike ZedlerAbstract:As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo. In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes. The skin acts as an important first barrier of the body, which is constantly exposed to diverse environmental and mechanical insults, such as pollution, infection, injury and radiation, amongst others 1. Additionally, the application of cosmetics and other agents can have a major impact on skin homeostasis 1. Among the most widely used skin dyes, are the extracts of Lawsonia inermis, commonly known as Henna 2. In traditional medicine, Henna has been widely used to treat bacterial and fungal infections, inflammation, cancer and various skin pathologies 3 , but the underlying mechanisms remain insufficiently understood. Major side effects of Henna preparations are caused by the additive para-phenylenediamine (PPD) that has been associated with allergic contact dermatitis 4,5. As natural product, Henna comprises a mixture of numerous compounds most of which are poorly characterized opeN There are amendments to this paper
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The Henna pigment Lawsone activates the Aryl Hydrocarbon Receptor and impacts skin homeostasis
Scientific Reports, 2019Co-Authors: Laura Lozza, Pedro Moura-alves, Teresa Domaszewska, Carolina Lage Crespo, Ioana Streata, Annika Kreuchwig, Andreas Puyskens, Marina Bechtle, Marion Klemm, Ulrike ZedlerAbstract:As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. Tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo . In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes.
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The Aryl Hydrocarbon Receptor senses the Henna pigment Lawsone and mediates Yin-Yang effects on skin homeostasis
2018Co-Authors: Laura Lozza, Pedro Moura-alves, Teresa Domaszewska, Ioana Streata, Annika Kreuchwig, Marina Bechtle, Marion Klemm, Ulrike Zedler, Carolina Lage Crespo, Silviu Ungureanu BogdanAbstract:As a first host barrier, the skin is constantly exposed to environmental insults that perturb its integrity. Tight regulation of skin homeostasis is largely controlled by the aryl hydrocarbon receptor (AhR). Here, we demonstrate that Henna and its major pigment, the naphthoquinone Lawsone activate AhR, both in vitro and in vivo. In human keratinocytes and epidermis equivalents, Lawsone exposure enhances the production of late epidermal proteins, impacts keratinocyte differentiation and proliferation, and regulates skin inflammation. To determine the potential use of Lawsone for therapeutic application, we harnessed human, murine and zebrafish models. In skin regeneration models, Lawsone interferes with physiological tissue regeneration and inhibits wound healing. Conversely, in a human acute dermatitis model, topical application of a Lawsone-containing cream ameliorates skin irritation. Altogether, our study reveals how a widely used natural plant pigment is sensed by the host receptor AhR, and how the physiopathological context determines beneficial and detrimental outcomes.